Dynamic and static mixers are known in the art. Conventional dynamic mixers include two elements, which are rotatable relative to each other and include a flow path extending between an inlet for materials to be mixed and an outlet. Dynamic mixers use an electric motor to drive the rotatable elements, for example propellers, in order to mix fluid compositions. Such dynamic mixers can be expensive to purchase and maintain as they include electrically driven, moving parts and require large amounts of energy to operate.
In contrast, static mixers are widely available and do not include moving parts and do not require large amounts of energy to operate. Static mixers include fixed position structural elements that are generally mounted such that fluids passing through the elements may be effectively mixed or blended with a wide variety of additives. Such mixers have widespread use, such as in municipal and industrial water treatment, chemical blending and chlorination/de-chlorination facilities, to name but a few.
One type of static mixer is a pipe static mixer, where the structural elements are mounted within a conduit and the conduit is connected to a pipe system. As a result, such mixers are located within a closed environment. A highly effective, commercially available pipe static mixer is described in applicant's previous U.S. Pat. No. 5,839,828 issued Nov. 24, 1998 to Robert W. Glanville. The '828 patent discloses a device (10) having a circular flange (14) which is designed to be mounted internally within the pipe (24). The flange (14) includes a central opening which (22) having flaps (18) that extend radially inward within opening (22). The device when mounted within pipe (24) enables an effective mixing to be achieved downstream of the device. The teachings of U.S. Pat. No. 5,839,828 are hereby incorporated into the present specification in their entirety by specific reference thereto. An additional commercially available pipe static mixer is described in applicant's previous U.S. Pat. No. 8,147,124 issued Apr. 3, 2012 to Robert W. Glanville. The '124 patent discloses a static mixing device (10) for mounting within a hollow tubular conduit, the device including a plurality of vanes (14) generally equally spaced within the conduit, each vane including a generally oblong plate member (18) radially inwardly extending from the conduit internal wall surface (16) and having a generally wing-shaped cap (40) that downwardly, rearwardly and inwardly bends from the top of the plate to the internal conduit wall. The teachings of U.S. Pat. No. 8,147,124 are also hereby incorporated into the present specification in their entirety by specific reference thereto.
One application for static mixers is in open channels, such as water treatment channels for wastewater. In conventional open channel static mixers, the structural elements are mounted directly within an open channel and flow is directed through the mixers within the open channel. Typically, these structural elements are intended to be permanently mounted in the open channel and are typically large and heavy elements. As a result, installation and removal can be difficult and expensive, often requiring large equipment, such as cranes to install the elements.